1. Field of the Invention
The present invention relates to an ink jet system and a method for removing an air bubble from the inside of an ink jet nozzle.
2. Description of the Related Art
An ink jet printing method is used for spraying fine droplets of ink directly onto a printing medium, so as to print indicia thereon. The ink can be sprayed onto the print medium by use of a simple mechanism, and therefore, the method can be utilized in various fields. For example, in the field of semiconductor technology, an ink jet print system has become a focus of attention as a technique for forming a pattern on a liquid crystal.
In the case where a pattern is formed on a liquid crystal by the resist, many processes are required, including mounting a cap on the liquid crystal, followed by etching, and the like. In contrast, when ink is applied by an ink jet device, the pattern can be formed directly on a liquid crystal substrate without either a cap mounting process or an etching process. As a consequence, the processes can be simplified and the amount of organic solvent can be reduced. Thus, a method of applying ink using an ink jet device has becomes a focus of attention in the field of semiconductor technology.
In this case, in order to form a high density pattern, ink needs to be sprayed in a fine pitch. However, if an air bubble adheres to a nozzle side surface of a nozzle plate in the ink jet device, the ink cannot flow straight, thereby making it difficult to apply the ink in a fine pitch.
One way of solving the above-described problem, for example, is to introduce gas to flow into an ink supply tank containing the ink before use of the ink, followed by degassing, so as to inhibit the gas from intruding into the nozzle. However, gas contained in the ink as an air bubble could not be completely prevented from flowing into the nozzle. As a result, the ink jet device was disassembled, and then, the inside of the nozzle of the nozzle plate was cleaned to wash out the air bubble. Therefore, problems arose as to complicated work processing and degradation of continuous operation of the device.
Hence, a method for removing an air bubble from inside the ink jet nozzle has been demanded.